flaky residential router

[David Curtis]

On 2/9/11, Thufir Hawat <hawat.thufir at gmail.com> wrote:
> I have a strange, intermittent, connection problem.  Oddly enough, the
> wireless part of the router seems to work fine.  However, the computer
> will periodically experience connectivity problems only solved by a
> reboot.
>
> I try:
>
> ifconfig eth0 down; ifconfig eth1 down; ifconfig eth0 up; ifconfig eth1
> up; ifconfig; ping 192.168.1.1
>
>
> and the router's available, however I cannot ping google.com, I get
> "network unavailable" which, given that the wireless connection is
> working, this is kinda odd.  (Yes, the wireless is connected to my
> router, not to my neighbors -- I double checked.)
>
> I've tried powercycling the router, but get the same result as above.
> However, restarting the computer allows a reconnection.
>
> Obviously, I need to replace the router.  However, that doesn't explain
> what's going on.  Why would restarting the computer have any effect?  If
> I was on Windows, I'd suspect corrupted system files or something along
> those lines.
>

Is the default route wired or wireless? (eth0 or eth1). Are you using
network manager?

Try just bringing up the wireless by itself. But if you do use NM run
through the settings and set the wireless as default route. It could
be Ubuntu's trying to use the wired as default and doesn't use the
wireless.